Geared ratchet wrench



June 15, 1954 MlLLER 2,680,983

GEARED RATCHET WRENCH Filed June 2a, 1953 Fig. I

W if Y I k H32 20 I2 38 so Q Fig. 3

INVENTOR. JE 'RRY T. MILLER 36 mm 8r mm) AGENTS FOR APPLICANT PatentedJune 15, 1954 UNITED STATES GEARED RATCHET WRENCH Jerry T. Miller,National City, Calif. Application June 23, 1953, Serial No. 363,432

3 Claims. 1

The present invention relates generally to wrenches and moreparticularly to a geared ratchet wrench.

The primary object of this invention is to provide a ratchet wrenchhaving reduction gears in the driving head to increase the torque of thewrench without increasing the size.

Another object of this invention is to provide a geared ratchet wrenchwhich may be used with many types of conventional interchangeable socketheads and the like.

Another object of this invention is to provide a geared ratchet wrenchhaving a compact, dependable and easily accessible reversing meanscombined with the reduction gear mechanism.

Another object of this invention is to provide a geared ratchet wrenchwhich is adapted for fabrication from many different materials, so thatthe choice of material can be according to the dictates of availabilityand price considerations, the exact sizes and proportions being matterseasily determined to suit particular conditions and needs.

Another object of this invention is to provide a geared ratchet wrenchwhich is inexpensive and 1 practicable to manufacture.

Finally, it is an object to provide a geared ratchet wrench of theaforementioned character which is simple, safe and convenient tooperate, and which will give generally efiicient and durable service.

With these and other objects definitely in view, this invention consistsin the novel construction, combination and arrangement of elements andportions, as will be hereinafter fully described in the specification,particularly pointed out in the claims, and illustrated in the drawingwhich forms a material part of this disclosure and wherein similarcharacters of reference indicate similar or identical elements andportions throughout the specification and throughout the views of thedrawing, and in which:

Fig. 1 is a plan view of the wrench.

Fig. 2 is a sectional view taken on the line 2-2 of Fig. 1.

Fig. 3 is an enlarged sectional view taken on the line 3-3 of Fig. 2.

Fig. 4 is a sectional view taken on the line 4--4 of Fig. 3.

Fig. 5 is an enlarged sectional view similar to Fig. 3 but showing onlythe ratchet mechanism for clarity.

Referring now to the drawing, the wrench includes a gear head It whichcomprises a casing 12 and a cover plate l4. Within the casing it are adriven gear 16 and a pinion or smaller drive gear I 8 enmeshedtherewith, the driven gear having a square shank 23 which projectsthrough the casing and constitutes the drivng shaft for the socket head22. The ratchet mechanism 24 is contained in the drive gear 18, fromwhich a shaft 25 extends upwardly and is fitted with a handle 28.

The cover plate i4 is secured to the casing l2 by means of rivets 39 orthe like to maintain an effective seal against foreign matter ormoisture. The driven gear It has a shoulder 32 which bears on thecasingIZ, said driven gear being aligned by a pin 34 which is secured inthe shank 2c and is journalled in the cover plate l4. The drive gear [8has a shoulder 36 which bears on the casing !2, said shoulder having anextended stub shaft 38 journalled in the casing to en sure accuratealignment of the gears. The gear train may include three or more gears.

The drive gear I8 is provided with a serrated bore 49, the serrationsserving as ratchet teeth 42. On the lower end of the shaft 25 is atubular hub 44 which is positioned concentrically in the bore 49, saidhub having a pair of adjacent slots 46 through which the pawls 4B and 49extend. These pawls 48 and 49 have chamfered ends 59 which engage theratchet teeth 42, and are slidably mounted in the hub 44. The pawls arealigned by means of locating pins 52 embedded in the hub 44, said pinsbeing keyed in longitudinal slots 54 in one edge of each pawl.

Extending axially through the shaft 26 and mounted therein for manualoscillation is a rod 56, at the upper end of which is fitted a lever 58.The lower end of the rod 56 is shaped to form a cam 60 having a pair ofadjacent flat faces 62 and 64 disposed substantially normal to eachother. These flat faces 62 and 64 may be brought to bear selectivelyagainst the pawls 48 and 49 by partial rotation of the rod 55 by meansof the lever 58. Thus each pawl may be locked securely against the outeredge of its slot 46 as illustrated in Fig. 5. The pawls 48 and 49 arebiased against the ratchet teeth 42 by a coil spring 66 fitted aroundthe rod 56, the ends of said spring resting against the rear edges ofsaid pawls.

If reference be had to Fig. 3, it will be evident that the pawl 48 isfree to move in the slot 46 so that the drive gear It may rotate freelyin a clockwise direction. However, the drive gear is prevented fromcounterclockwise rotation by the cam 60. By reversing the cam 60, thedirection of free rotation of the drive gear l8 may,

of course, be reversed, thus providing for reversible operation of thewrench. The reduction ratio of the gears enables considerable torque tobe applied to the socket head 22 with a comparatively small pressure onthe handle 28.

The operation of this invention will be clearly comprehended from aconsideration of the foregoing description of the mechanical detailsthereof, taken in connection with the drawing and the: above utecited"objects. It will be obvious that allsaidob'jects are amply achieved bythis invention.

Further description would appear to be unnecessary.

It is understood that minor variation from the form of the inventiondisclosed"herein may be made without departure from the spiritwand-scopeof the invention, and that the specification and drawing are to beconsidered as merely illustrative rather than limiting.

i I' fcl'aim: a Argeared ratchet-wrench:including: argear I:zheamisaid'geart head comprising a ;closed :casing,

s a i driverrsgeari Totata-bly :mounted :in: saicr easing,

at ;smaller.:drive gear, rotatably mounted in? said W asingi-and'enmeshed with :said driven gear; a ssricketr head removablwatta'ched'to? 'saididriven gear, said drive gear having a bore, said borehavfiringv a: plurality ofizinternal ratchet'teeth; areversisbleiratchet mechanism operatively engaging 'said aratchet:teeth;:anda; handle'toperatively connected "-to saida'atchetmechanism.

2.A-":geared? ratchet' wrench :includinga. gear ahead;saids-geartheadcomprising a closedxca'sing,

smaller drive= gearrrotatably mountedrin said erasing; BndffTIEnmeSh'BdWVlth said; 'driven gear; a ssockettehead removably:attached toa saiddriven asdrivxen'geait'rotatably 'mountediin'tsaict casing, 5

head-:- said gear'head comprising: a: closed casing, a drivengearrotatablymounted in "said casing,

a smaller drive gear rotatably mounted in said casing and enmeshed withsaid driven gear, a 1, socketfrhead removably attached to said drivengear, said drive gear having a bore, a hub concentrically mounted insaid bore, a pair of spaced -=pawls slidably and pivotally mounted insaid hub,

said pawls being selectively engageable with said -ratchet teeth, saidhub having an extended shaft,

a rod rotatably mounted axially in said shaft, a

camon the lower BIld'Of' said rod-,rsaidncani being "selectivelyengageable-s-withz said "paW1S SOZithat said pawls are selectivelylocked :againsts'said ratchetteeth; and a handle operatively connectedtosaid shaft.

References Citedain .thezfile or this: patent UNITED STATES PA'IENTS 30vNumber i Name 4- Date 417,829 Lowell 4 Dec. 24,1889

. 71,765 Weverretial. Mar; 29,1892

872,633 Anspach rJDecQ B, .1907

. 1,614,534 Norton.-e.\. s J an, 18,1927

.3 2,520,443 Seaquist v -..Augw29,. 1950 1,578,686 i Fishv Dec, 18,1951-2,'634,630

Johnson LApr.. 14, 1953

